What Breaks at what power levels?

I'm throwing this here in the Tuning section because in my experience True Calibrators know what is "Toonable" and what isn't as far as combinations go. I ordered a 22 ST back in Sept. for the wife's new commuter/Kid hauler/ grocery getter after doing a bunch of research with this platform. So far, the ST looks promising with potential to be a solid candidate for what she wants and will satisfy my requirements for driveability and supporting modifications to fit our outdoor lifestyle. I have the cosmetic details fairly pinned down she wants, but I am having a hard time time finding factual information about the drivetrain limitations. Just like any other new platform to market, it takes a while for the aftermarket to find the limits of stock parts before better, stronger and more efficient parts can be developed and tested. I have some questions, I've looked around and haven't found a solid source of information so, I'll ask here.

-What kind of bottom end is in this 3L? What kind of rods? Same goes for the pistons, rings, Crank , oil pump gears ect. What power levels are they showing their weaknesses? How is the timing chain system holding up? Including Heads, Valves, Springs, retainers ect. I guess, I'm asking whats is the over all durability of it?

-Transmission. Where are the current limitations of the converter, clutches, case, ect?

- Differential, Axles, drive shaft, ect? Are they breaking yet. What MPH are they handling? I'm not too concerned with the occasional CV boot grease leak I've seen here.

- Fuel System, Turbos? When are they running out on pump gas (91-93oct). We live in the Northwest @3500', E85 is not an option here. I know IAT's and heat soak become an issue with the factory intercooler just like most other factory boosted applications.

- Any other known failure points or failure thresholds known would be nice to know. I don't have much experience with the eco-boost stuff so, this is my first rodeo with them. These things remind me of the Typhoon, Syclone, T-Type, turbo 6 days when a 10 second car was fast. Any input would be great. Thanks

Crickets !!

You hear crickets since for the majority of people buying a 3 row SUV, a mid-hi 13s 1/4 mile with good handling is enough. A very small percentage have gone ahead and done a tune- which is enough for mid-hi 12s with no other mods. As far as I know, only a handful of people have actually pushed the platform to the point of breakage- most of those have been trans related, although I've heard (anecdotally) at least one killing the engine via oil starvation. If this engine platform was in a Mustang for example, you'd find a lot more people doing modifications and more info on weak links.

To be honest though, if you're only going to run 93, even with upgraded turbos you're going to have a very hard time getting past 600hp crank or mid-hi 11s without going into the engine- and then the price goes up substantially.

Believe me, I'm into modifying my car, but if I wanted to build a 10 second SUV for some reason other than bragging rights, I'd probably begin with something like a Trackhawk.

Are you talking two adults and five midgets in a trackhawk?

Do my five midget grandkids count? LOL, I'm just pointing out that I'd pick something that had a lot more cubic inches, forged internals, and a couple more cylinders.

A couple of things- the ST does have (info from interweb) a forged crank, forged rods, and piston squirters. @ZFGracing does have a thread on here about the 3.0 piston where he verifies the piston squirters. He considers the 3.0 piston as better than the Ford 2.7 which according to him had pin boss failure problems. So, the short block basics seem to have been covered pretty well.

It's a V6, so already you have less worry about the crank since it's probably only about 14 inches long and (also from internet) has 6 bolt mains. You now have dual timing chains, which were upgraded from the early 3.5 engines. As far as the heads, you have a roller-finger actuated DOHC drivetrain with hollow cams and hydraulic lash adjusters. So much of this is pretty much what you'd expect in a contemporary hi-performance engine.

If you're truly looking for big power, high boost applications, you'd have to address turbos (absolutely first), pistons (they aren't forged supposedly), the open deck block, and the inevitable head lifting (no idea what the head bolt sizing is on these). But all in all, a very good engine indeed and probably a little bit of overkill for 400hp.

But, you need to run 93 octane, which we know supports 415 lb/ft of torque. You could upgrade the valve springs to support 7500 rpm and turbos that would support stock levels of boost at that rpm/mass airflow level. That would get you to about 550hp @7000 rpm crank without the big boost numbers and without worrying about head lift.

Does that help?

And, just for grins, take a look at LokiWolf et al, putting down 500 lb/ft of torque on 93. If we had enough turbo (and other V/E improvements) to maintain that type of airflow at 7000 rpm we could estimate 500*7000/5252 or 666 hp on 93 pump gas!

What has been said seems to be correct. There isn't tons of info available on a car that's only been on the road a couple of years. One thing that I can't get out of my head is the "downgrade" for lack of a better term of support for the rear differential. My head says this could potentially be a weak link for brake torquing and then letting it go.

That change confuses everybody…makes no sense at all.

How long before we see an aftermarket carrier with dual high-durometer bushings address the issue? Hint, hint.

Edit so as not to extend this about differential probs, since there are two other threads on this matter. If you remember back to pre-pandemic on the 2020s, Ford was selling way more STs than expected. So, for 2021, they dropped certain amenities to make a bit more moolah or because of supplier issues. I can almost guarantee Ford has a bonus plan for engineers who come up with changes to save money. Seeing as how both the bushing AND the mount was changed (but not the diff cover- which is still threaded), someone did all the calcs to convince the powers-that-be the change was structurally sound.

That mount is meant to limit the movement of the rear end of the differential in a vertical and horizontal direction. If you only considered those- it's possible that a single bolt and mount might meet the specs. However, if you think about a twisting motion and torsional constraints, (especially since the single mount is now off center) it looks pretty sketchy. I think someone screwed up.

Had to have been to save $1.34 in production costs. Pretty disappointing.


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Prius engineers on the loose !

I think if you look at 3 row suvs in the same category, you won't see much different in terms of engine development or drivetrains. Land Rover, Audi SQ7, BMW X7, MB GLS, Durango Hellcat. Most of these start (or need to optioned enginewise) to beat the ST and are $25k to $75k more (and yes, they probably have nicer interiors).

But I don't think you can beat the ST value proposition. Also, most of these don't exceed 20mpg on their best day. This is my first Ford, but I recently returned from a 2000 mile trip with 5 other people plus luggage and we averaged nearly 24 mpg. This included 3 hour plus bumper to bumper traffic (both ways- gasp) in the 75 miles of Atlanta's torturing, soul-destroying traffic!

Ford Diablo - Catch it at a Ford dealer near you. Twin turbos from hell spitting out 666 hp from a baby V-6. Capable of jaw breaking acceleration and could toss any unsuspecting mother-in-law into the rear cargo area at will. Some exorcisms may be required. Ford Diablo. Copywrite 2021

Tmac Thanks and your right...There is a very small percentage of people pushing the platform and most of those are probably pretty secret squirrel about it trying to stay an edge up on whomever they are chasing down or trying to stay ahead of. I'm no stranger to pushing the limits breaking things, but over the 25+ years of doing it, I learned along time ago to avoid doing the stupid stuff that almost always leads to a major catastrophic failure which could of been avoided. Spend the money in the places it needs to be spent, period.

The response about the trans related failures (Not the factory issues)...That is the stuff I like to hear about. Power levels, driving conditions, what failed ect. I like to understand what was going on when it happened to try to decipher what caused the failure and address it. More of a technical point of view If that makes sense? I understand you probably dont know, but The oil starvation comment is the same way.

@UpinBst Probably at this stage, no one can truly answer your questions. But, by the time it's been out a few years, like every other enthusiast site, you'll get 100 different opinions for every failure!

In my mind, the engine is definitely if not state of the art, at least close, and Ford has been doing direct injected twin turbo v-6s for quite some time. The 3.0 has certainly benefited from 10+ years of work, so you could probably have a lot of confidence in it (as I do), but the 10R60 which was co-developed with GM has fairly new and from what I can see is much more suited to getting better mpg than being bulletproof. BTW, since you're new, the 10R60 supposedly means the 60 = 600 n/m of torque or about 442 lb/ft.

Thanks for the direction on the piston write-up in here, I found it. I had already found online the rods are steel and pistons were cast aluminum so it was nice to have an actual visual picture to look at.
The forged steel crank is of interest to me because I had seen somewhere that a guy claimed a flex plate failure and had custom (What I assume is SFI Approved) flexplates made to remedi a fix. After looking at the pictures online of the Giant hole in the back of the block from what I think was a 2nd failure after the new flex plate, I'm pretty sure the crank is broken and looks like a rod (or 2) were missing a piston behind it. IDK the pictures were blurry. Point being, just because its forged steel doesn't say much until we add the type and I highly doubt there is crankshaft available for this engine, yet. Also, if the rods are missing pistons, the crank is broken, the flexplate went round and round in the bell housing destroying the front of the trans...What went first? Did a piston break because of detonation from a over taxed fuel system?

I don't know, but direct me to the pics and I'll look. In a v6, because of the shortness of the crank, you just don't see them break unless there was catastrophic failure elsewhere. The last think I'd do is run out to Callies to have them build me a billet version just because I saw something on the web.

New to the site, not new to Ford though, thanks. The whole point is trying to open up quality dialogue about failures and limitations to get up to speed of where the market is right now on the 3.0 platform. Basically sorting through all the BS

That's a sobering thought.